Who Will Fund Start-Up Pot Businesses?

Most cannabis-related investment advice I've seen seems to distill down to this: Avoid companies that actually sell pot and instead invest in "ancillary" businesses—such as the hash-oil-machine maker, pot-selling software, and web-based weed advertising services. The typical reasoning for this reservation is the big federal question mark, the uncertainty about whether the Feds might start forfeiture proceedings against legal pot investments.